A nanowire is a nanowire structure having a size in a unit of nanometer and has various sizes from less than 10 nm in diameter provided with general nanowire to several hundred nm. The nanowire is advantageous in that an electromigration property according to a specific direction or an optical property showing polarization can be used. Thus, it is a next generation technology which has been widely applied into various fields of an optical device such as a laser, a transistor, a memory device and the like.
However, a research on a method of manufacturing a nanoparticle and a physical property thereof has been considerably revitalized. In comparison, a research on a method of manufacturing a nanowire lacks. A representative conventional method of manufacturing the nanowire is a method of growing a nanowire metal using a catalyst and a method of forming the nanowire using a template. First, as the method of forming the nanowire material using the template, there are a method of producing an alumina membrane composed of holes having, several dozens nm in diameter and several μm in depth through anodizing, and thereafter filling a nanowire material with the holes, and a method of making the nanowire material in a gas state and depositing it in the holes. Specifically, a technology relating to a method of manufacturing a nanowire using a template, U.S. Pat. No. 6,525,461 describes a technology for forming a titanium nanowire in a pore by forming a catalyst film on a substrate, and forming a porous layer at an upper part to conduct heat treatment. Also, as a technology relating to a method of manufacturing a quantum dot solid using a template, U.S. Pat. No. 6,139,626 describes a technology of forming a quantum dot solid by injecting the colloidal nanocrystals into pores formed in a template and conducting heat treatment. However, the method of manufacturing the nanowire based on the above technology is problematic because the process is very complex and slow, it is not suitable for mass production. Furthermore, it is problematic because it is difficult to control uniformity, the nanowire having excellent straightness and arrangement can be formed.
As the method of growing the nanowire metal using a catalyst, there is a laser assisted catalytic growth (LCG) method or a vapor liquid solid (VLS) growth method described in Korean Laid-Open Patent Publication No. 10-2006-0098959. That is, there a method of growing the nanowire using a nanowire material and a mixture of metals as a raw material, and a metal catalyst as a core. However, the aforesaid method is problematic in that the nanowire has a limit to the formation of the largest length, and high temperature heat treatment process is necessarily required, so it is not suitable for the mass production. Also, in the case of the vapor liquid solid (VLS) growth method, the growth of the nanowire is limited by a diameter of the metal catalyst and a distribution thereof. The method also is problematic in that it is difficult to accurately adjust the width (thickness) and the distribution and contamination is generated due to the metal catalyst in the nanowire. In addition to this, the vapor liquid solid (VLS) growth method has a limit to produce the nanowire in large quantities because equipment used for the method has a high price, a process cost is also high, and because a growing time is slow, a mass production ability is low.
That is, the most methods of manufacturing the nanowire which were already known are not suitable for manufacturing the nanowire having an excellent physical property. in large quantities with a low expense. Thus, the development of a new method of manufacturing the nanowire has been required.